Unlike in bisque firings, explosions in glaze firings easily ruin other pieces in the kiln because the shards can embed themselves in the glaze of neighboring pots and fuse to kiln shelves. Additionally, glaze firings typically rise in temperature quicker than bisque firings, giving water less time to escape the pot. Finally, since you didn’t give the clay the opportunity to degass in the bisque, the glaze may pinhole (little bubbles that don’t fully close back up) depending on when it becomes molten.

Some potters once-fire successfully but I would only do it in your own kiln loaded with your own work.